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IT Tech

Notes on technical concepts and tools.

IT Tech

Moving Time Capsule backups to SMB on macOS 27

macOS 27 dropped the AFP client and ended Time Machine backups to a 4th-generation Time Capsule. How TimeCapsuleSMB restored them over SMB3, and the risks.

IT Tech

A contract for counting ad impressions the same way on three platforms

A finished load on iOS, an impression callback on Android, a DOM mount on the web: one name, three meanings. A contract that splits the stages of an ad.

IT Tech

Daily puzzle scores: which day they belong to and how they get lost

In a game started at 23:50 and finished at 00:05, the puzzle date, the submission time, and the leaderboard window can disagree. How far to guarantee delivery.

IT Tech

Ordering ad providers by GeoIP region without the location permission

When ad providers differ by region, an app needs a broad region, not coordinates. Consent first, then a server-side region bucket decides the provider order.

IT Tech

Verifying a verification script with deliberately broken input

A check script that exits with status 0 has not necessarily checked the rule. Break one thing in a copy of a good sample and confirm the expected category.

IT Tech

Who watches the watcher: finding a scheduled job that vanished

A deleted scheduled job leaves no error. Compare the expected roles with what the scheduler really holds, and alert on the time of the last success.

IT Tech

Rust shared core, part 7: splitting tests and CI by layer

Passing Rust tests still leaves iOS linking, Android release ABIs, and Wasm loading in web builds to break. Test the domain in Rust and build fresh in CI.

IT Tech

Rust shared core, part 6: using it on the web as a Wasm package

To use the Rust rules from mobile on the web, compile them to WebAssembly and ship a package. Roles, where to initialize in Next.js, and the call contract.

IT Tech

Rust shared core, part 5: what to check when shipping a .so on Android

Generating Kotlin bindings does not finish Android integration. Per-ABI .so placement, wiring Rust into Gradle, the 16 KB page rule, and release checks.

IT Tech

Rust shared core, part 4: delivering it to iOS as an XCFramework

Passing Rust tests does not mean an iOS app links. Bundle device and simulator static libraries into an XCFramework, ship it as a Swift package, and align CI.

IT Tech

Xcode UI tests and what automationmodetool does and does not cover

When Xcode UI tests stall at an authentication prompt on an unattended Mac, automationmodetool covers one part and TCC permissions another. Here is how to tell.

IT Tech

Rust shared core, part 3: keep UniFFI generated code behind an adapter

UniFFI generates Swift and Kotlin calling code from Rust. What to expose and how far generated types spread is up to the app. An adapter keeps them contained.

IT Tech

DevToolsSecurity on macOS and debugger authorization on unattended CI

Attaching a debugger on a Mac can show a password prompt, and unattended CI stalls on it. What DevToolsSecurity changes, read directly on macOS 27.0.1.

IT Tech

Why Hangul file names fall apart into jamo, and how NFC fixes it

A Hangul file name made on macOS can look decomposed or count as a different name elsewhere. The cause is the Unicode normalization form, checked with code.

IT Tech

Rust shared core, part 2: keep the API across the boundary coarse

Types that suit a Rust engine differ from types that are easy to use from Swift, Kotlin, and TypeScript. Expose coarse action-level functions under a contract.

IT Tech

Rust shared core, part 1: what to share and where to draw the line

Building for iOS, Android, and the web means writing the same rules three times. Narrow what Rust shares to rules that must give the same result, in 3 layers.

IT Tech

What to decide when registering fonts at runtime on iOS

Bundled fonts need only an Info.plist entry, but downloaded or packaged fonts may suit runtime registration. This covers names, a registry, and file lifetime.

IT Tech

What to look at before adopting a Swift package registry

Receiving Swift dependencies by registry ID changes the path they travel. Request order, configuration, mixed graphs, mirrors, authentication, and signing.